This application claims the priority of German application 196 19 183.1, the disclosure of which is expressly incorporated by reference herein.
The present invention relates to a cylinder head arrangement of an internal-combustion engine, and more particularly, to an engine cylinder head arrangement comprising a plurality of housing components including a basic housing placed on a cylinder block, a cylinder head cover and a support component configured to accommodate valve stroke transmitting elements, at least two common junction planes between two of the housing components, which rest against one another with respective flange surfaces thereof, and oil supply ducts.
DE 43 24 791 A1 describes a cylinder head arrangement which consists of a basic housing placed on the cylinder block, a support component inserted into the basic housing and a closingoff cylinder head cover. The support component is used for accommodating valve stroke transmitting elements constructed as bucket tappet elements. This support component is inserted into the basic housing. The cylinder head arrangement is closed off toward the top by a cylinder head cover which is placed in a common junction plane on flange surfaces of the exterior walls of the basic housing and onto a flange surface of the support component. In this common junction plane, the oil supply ducts are constructed as indentations within the flange surface and are combined to form an oil gallery and are used for supplying oil to the valve stroke transmitting elements.
Another cylinder head arrangement is described in DE 43 07 368 A1, within which five charge cycle valves respectively for each cylinder are guided in the basic housing. Three of these charge cycle valves are inlet valves and two are outlet valves. The valve stroke transmitting elements are guided or disposed on the support component, with the two outlet valves per cylinder being operated by bucket tappet elements. Two of the three inlet valves are also acted upon by bucket tappet elements which via a suitable control can influence the valve stroke of the assigned charge cycle valve. The third inlet valve is operated by an operating lever guided on the support component. In a cylinder head arrangement of this type, many bearing areas and sliding surfaces must be supplied with the lubricant (oil) because of the large number of moved constructional elements. Furthermore, if the switchable valve stroke transmitting elements are acted upon hydraulically and, as is usually the situation, are also supplied by way of the oil supply of the internal-combustion engine, multiple problems occur with respect to the overall oil supply to the cylinder head.
It is, therefore, an object of the present invention to improve the oil supply within a cylinder head arrangement such that the latter can be manufactured in a simple manner and at low cost, and permits an at least partially independent supplying of different consuming devices. In this arrangement, the bore expenditures within the cylinder head arrangement are minimized and, in particular, very long and cost-intensive and labor-intensive oil bores are avoided.
According to the invention, this object has been achieved by providing that in each of the at least two junction planes, grooves are formed in at least one of the assigned flange surfaces and constitute the oil supply ducts which form at least two oil galleries for supplying separate consuming devices.
Within two junction planes of the cylinder head arrangement, oil supply ducts are formed which are combined to form one oil gallery respectively. These oil supply ducts are shaped by grooves machined into the flange surfaces and form two oil galleries. From these oil galleries, a large number of consuming devices within the cylinder head arrangement can be supplied with oil.
In this arrangement according to the present invention, bores, whose manufacturing requires high expenditures and which are costly, are largely avoided. By dividing the oil supply within the cylinder head arrangement into at least two oil galleries, different consuming devices can be supplied. This becomes possible in particular as the result of the corresponding further feature of the individual oil supply ducts and a suitable connection with the oil supply of the cylinder block, differences are possible in the delivery volume and the pressure.
In an especially advantageous manner, a first oil gallery can be constructed in the junction plane between the basic housing and the support component and can be connected along a particularly short path with the oil supply within the cylinder block. If such a first oil gallery is supplied by way of known ascending pipes within the cylinder block, a very direct linking is possible which requires very few bores and thus also keeps the throttling losses low.
The second oil gallery can advantageously be formed in the junction plane bounded by the cylinder head cover so that a spatial separation is achieved with respect to the first oil gallery. Thus, the supply of a large number of consuming devices is provided in a simple manner which is free of intersections.
The supply of different consuming devices which make different demands with respect to the oil volume and/or the oil pressure is achieved in a particularly advantageous manner in accordance with the present invention in that within one oil gallery formed in the respective junction plane, two or more individual supply branches are formed. These supply branches can be arranged in a particularly simple manner to extend in each case in the longitudinal direction of the cylinder head arrangement and are constructed in different flange sections of the respective flange surface.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.